Question

State the functions of gustatory receptors and olfactory receptors.

Answer 1

Hint: Gustatory and olfactory receptors are the sensory receptors that are related to the sense of taste and sense of smell respectively.

Complete answer:
Gustatory receptors- They are present on the papillae of the tongue and are spread evenly across the taste buds.
- Their main function is to provide a sense of taste.
- The cranial nerve IXth i.e. the Glossopharyngeal nerve carries the sensory stimulation of taste to the brain.
- The primary tastes detected by humans are sweet, sour, bitter, salty, and umami.
Olfactory receptors- They are present on the surface of the olfactory epithelium at the upper 2/3rd of the nasal cavity.
- Their main function is to sense smell.
- The sensory reception of smell is carried to the brain from the olfactory epithelium through - the Olfactory nerve (1st cranial nerve).
- These receptors equip sperm cells for finding the egg through a sense of smell.
- Humans have about 12 million olfactory receptors.

Note:
1. Olfactory stimulation is the only sensory information that directly reaches the cerebral cortex, whereas other sensations are relayed through the thalamus.
2. The tongue contains 4 types of papillae, namely Fungiform, Circumvallate, Filiform, and the foliate papillae. The most common type, filiform, do not contain taste buds.
3. The senses of smell and taste combine at the back of the throat.
4. Both olfactory and gustatory power declines with age.